Hepatitis Screening Suboptimal, Improving in Those Receiving Rituximab

A study of patients receiving rituximab therapy found that screening for hepatitis B virus infection (HBV) was suboptimal, and some patients who did not receive antiviral treatment experienced HBV reactivation or flare. Screening rates, however, do appear to be improving over time.

HBV reactivation is relatively rare in general, but it can lead to acute liver failure and death in as many as 25% of patients. “The risk of HBV reactivation can be as high as 50% in HBV surface antigen [HBsAg]-positive patients who are receiving immunosuppressive therapies, with the highest risk associated with anti-CD20 monoclonal antibodies like rituximab,” wrote study authors led by Robert J. Wong, MD, MS, of the Alameda Health System-Highland Hospital in Oakland, California.

The American Association for the Study of Liver Disease and other professional associations recommend universal HBV screening for all patients before receiving immunosuppressive therapy. The US Food and Drug Administration also now recommends screening for HBsAg positivity and/or HBV total core antibody (HBcAb) positivity.

The new study examined rates of HBV screening before rituximab therapy in a large, urban, safety-net hospital setting. It included 244 consecutive adults who received rituximab therapy between 2006 and 2015. The results were published in Cancer.

Overall, 75.7% of patients were screened for HBsAg, 61.3% were screened for HBcAb, and 60.1% were screened for both. Four patients (2.2%) tested positive for HBsAg, and 32 patients (21.5%) tested positive for HBcAb; only one was positive on both tests.

Of the four who tested positive for HBsAg, only one began antiviral therapy as a result. Seven of the 32 HBcAb-positive patients (21.9%) began antiviral therapy. The one patient positive on both tests also began therapy.

None of the three untreated HBsAg-positive patients experienced a flare. Two of 25 patients (8%) who screened positive for HBcAb and did not receive therapy developed HBV flares. Two of the 56 patients who were not screened (3.6%) developed HBV reactivation, and this was fatal in one of the patients. Among all patients who completed HBV tests before or soon after starting rituximab and who did not receive antiviral therapy, HBV flares occurred in 28.6% of HBsAg-positive patients, and HBV reactivation occurred in 7.4% of HBsAg-negative/HBcAb-positive patients.

The rates of screening did rise significantly over time, from 14.7% during the period from 2006 to 2009 to 74.7% from 2010 through 2012, and to 87.1% from 2013 through 2015 (P < .01). Those with hematologic or oncologic reasons for rituximab therapy were less likely to undergo HBV screening compared with those receiving the drug for rheumatologic conditions (P = .015).

“Despite improvements in HBV screening before rituximab, prophylactic initiation of HBV antiviral therapy in patients with HBsAg-positive or HBcAb-positive serologies remains low, and significant risks of HBV reactivation flares exist,” the authors wrote, and recommended targeted education and quality-improvement programs to increase provider use of HBV screening.